Commit e39c4575 authored by Devyn Liu's avatar Devyn Liu Committed by Xinghai Cen
Browse files

gpiolib: acpi: Fix failed in acpi_gpiochip_find() by adding parent node match 

mainline inclusion
from mainline-v6.11-rc1
commit adbc49a5a8c6fcf7be154c2e30213bbf472940da
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IAQ1MS
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git/commit/drivers/gpio/gpiolib-acpi.c?h=spi-v6.11&id=adbc49a5a8c6fcf7be154c2e30213bbf472940da



--------------------------------

Previous patch modified the standard used by acpi_gpiochip_find()
to match device nodes. Using the device node set in gc->gpiodev->d-
ev instead of gc->parent.

However, there is a situation in gpio-dwapb where the GPIO device
driver will set gc->fwnode for each port corresponding to a child
node under a GPIO device, so gc->gpiodev->dev will be assigned the
value of each child node in gpiochip_add_data().

gpio-dwapb.c:
128,31 static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
			       struct dwapb_port_property *pp,
			       unsigned int offs);
port->gc.fwnode = pp->fwnode;

693,39 static int dwapb_gpio_probe;
err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i);

When other drivers request GPIO pin resources through the GPIO device
node provided by ACPI (corresponding to the parent node), the change
of the matching object to gc->gpiodev->dev in acpi_gpiochip_find()
only allows finding the value of each port (child node), resulting
in a failed request.

Reapply the condition of using gc->parent for match in acpi_gpio-
chip_find() in the code can compatible with the problem of gpio-dwapb,
and will not affect the two cases mentioned in the patch:
1. There is no setting for gc->fwnode.
2. The case that depends on using gc->fwnode for match.

Fixes: 5062e4c1 ("gpiolib: acpi: use the fwnode in acpi_gpiochip_find()")
Fixes: 067dbc1e ("gpiolib: acpi: Don't use GPIO chip fwnode in acpi_gpiochip_find()")
Signed-off-by: default avatarlujunhua <lujunhua7@h-partners.com>
Signed-off-by: default avatarDevyn Liu <liudingyuan@huawei.com>
Reviewed-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: default avatarBenjamin Tissoires <bentiss@kernel.org>
Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
parent a3930c80

drivers/gpio/gpiolib-acpi.c

+17 −1
Original line number Diff line number Diff line
@@ -95,7 +95,23 @@ static bool acpi_gpio_deferred_req_irqs_done; 


static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)

{

	return device_match_acpi_handle(&gc->gpiodev->dev, data);

	/* First check the actual GPIO device */

	if (device_match_acpi_handle(&gc->gpiodev->dev, data))

		return true;



	/*

	 * When the ACPI device is artificially split to the banks of GPIOs,

	 * where each of them is represented by a separate GPIO device,

	 * the firmware node of the physical device may not be shared among

	 * the banks as they may require different values for the same property,

	 * e.g., number of GPIOs in a certain bank. In such case the ACPI handle

	 * of a GPIO device is NULL and can not be used. Hence we have to check

	 * the parent device to be sure that there is no match before bailing

	 * out.

	 */

	if (gc->parent)

		return device_match_acpi_handle(gc->parent, data);

	return false;

}



/**